Rebuilding a 96' 12 valve. The owner wants zero leaks

SCHMITTY

SCHMITTY

Not enough time
I've built a few marine v8 motors and Subaru along with a dozen or so transmissions. I've only had a couple tranny rebuilds leak and that was usually the dip stick hole- easy fix. This is my first cummins rebuild and the owner is sticking it in a 54' power wagon and kept bringing up leaks. I know my 95 leaks from all over the place.

Any areas to give special treatment to ? I'll buy some speedy sleeves if the crank needs them.

Starting to build a sweet stand tonight. I'm copying one off of CF. hopefully I can start it on the stand.
 
I've had good luck using loctite hi tack on gaskets mated to imperfect sealing surfaces

Leak free stock tappet covers on my rigs using hi tack.

Guy on eBay was selling improved rear main seals
 
I use loctite aviation sealer. Only had one mishap.

I second the crank case pressure sentiment

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I'll check out those sealants. I have been using the permatex white thread sealant with good luck on some fuel fittings and transmission bolts. Sometimes I use a light coat of the "right stuff" and clean any little bit of extra that may push out.

I'll look into venting the crank case better also
 
Permatex has an aviation variant of their 'Form-a-Gasket' sealant. It was recommended to me by an engine builder who has had very good luck with it over many years and uses. It's pretty tacky stuff and is doing the job on my engine.

I'll cast a vote for crankcase ventilation.

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It's been awhile since I've looked for my own use at upgraded crank case vent upgraded.

What type is that in the photo ?

24v has a better style also right ?

I'll do some research. I know my truck needs something also. It has 300k miles and when I'm over 50 psi boost the tailgate get oil droplets from the factory breather tube. I stuck a k&n style breather on my oil fill tube and by the time I got home from the parts store it had blown the top off the breather.
 
Those valve covers are used on engines built for industrial or agricultural applications. Cummins Dual Valve Cover Breather Kit 5.9L Diesel 12 Valve

The more filter elements, the better. You can use the breather that the 24v engines use in conjunction with anything else, of course. That's the breather that threads onto the timing cover, taking place of the oil fill tube and the hose runs straight down from it.
 
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Yes he is, same as I'm doing, I went with the billet tappet cover also
Use two vented valve covers and plug the tappet cover vent.

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Once you have the vented valve covers you want to plug the vent tube on the tappet cover.
That will stop one leak, you won't need a catch can for the vent hose on the vented valve covers.
 
Destroked 450 said:
Once you have the vented valve covers you want to plug the vent tube on the tappet cover.
That will stop one leak, you won't need a catch can for the vent hose on the vented valve covers.
Click to expand...

Do the valve covers come with some type of steel wool under the plastic part to catch the oil?
 
He's putting the motor in a 54' power wagon. He wants it extra clean. I'm sure if it drips from the breather hose a little he can throw a catch can on. The seals are my main concern and other leak prone areas. So extra CCV , aviation sealer on the tappet cover and timing cover ?

Is there a preffered ring gap ? I down loaded one manual(haven't read it yet).
 
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